The Proteomics Core was established in 2003 to address the needs of Center members to examine protein expression, interaction, and post-translational modifications as part of the molecular basis of cancer. The characterization of proteins and analysis of patterns of protein expression and modification will play a critical role in diagnosis and treatment of disease. Gene expression profiling can only provide a partial answer to the molecular aspects of cancer, because proteins are the ultimate mediators of gene function. The Proteomics Core provides investigators with expertise, protocols, and instrumentation to support protein and peptide separations, robotic sampling and digestion, as well as protein and peptide mass analysis. Furthermore, via collaboration with Cancer Informatics, we support data systems, software, and bioinformatics tools for data analysis and archiving. The individual services are grouped into modules for the ease of the collaborator; platforms are provided for protein identification, post-translational modification analysis, and quantification. Since the last submission, the Proteomics Core has added several new personnel, including two staff scientists. Several instruments have been added to the Core, including a second LTQ linear ion trap mass spectrometer (Thermo), an LTQ-Orbitrap upgrade (Thermo), a Symphony peptide synthesizer (Protein Technologies), and a ProPrep 11 (Digilatj) robot for automated sample handling, including protein.digestion, clean up, and MALDI spotting. A variety of new services have also been introduced including standard procedures and charges for separations and the implementation of quantitative mass spectrometry methods. Most significantly, the Core has fully implemented the reaction monitoring techniques on the triple quadrupole mass spectrometer. The Core's educational focus has expanded with the creation of a Clinical Proteomics Training Program, which enables the Core to train underrepresented undergraduate students. The Core requests CCSG Support of $191,446, which is 30% of its operational budget. Over 93% of usage is by Moffitt members and peer-reviewed.